/*
 * Copyright 2005 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.drools.core.util;
import java.util.Collection;

import org.drools.core.util.Queue.QueueEntry;

public interface Queue<T extends QueueEntry> {
    void enqueue(T queueable);

    T dequeue();
    void dequeue(T activation);

    boolean isEmpty();

    void clear();

    Collection<T> getAll();

    int size();

    T peek();

    interface QueueEntry {

        void setQueued(boolean b);

        int getQueueIndex();

        void setQueueIndex(int index);

        void dequeue();
        boolean isQueued();
    }
}
